Within the oil and gas industry, formation of a string begins on the floor where joints of pipe are assembled. The floor is a relatively small work area where pipe is added to or removed from the string. Some consider the floor to be one of the more dangerous locations on a rig as large heavy metal pipes are in close contact with rig crews and pipes are being lifted every 30-40 seconds at a substantially fast rate.
Generally, the work floor of a drilling/workover rig may be elevated above a pipe rack. Transfer of pipes from the pipe rack to the work floor is a delicate process requiring careful handling. Pipes are generally stacked on the pipe rack. To transfer a pipe from the pipe rack to the work floor, the pipes are generally rolled onto a boom arm that is raised up to the work floor. For example, exemplary systems for transferring a pipe from pipe racks to work floors are described in U.S. Pat. Nos. 7,163,367 and 7,021,880 which are hereby incorporated by reference in their entirety. Such systems raise an end of the boom to the work floor; however, each system includes pre-determined heights or a single set height at which to raise the boom. For example, the height of the boom may be set at pre-determined spacings from a horizontal plane to the work floor. Not all work floors, however, are at the same height. Even further, in such systems, height is not automatically adjustable during use as spacings are pre-determined.